1. Field of the Invention
The present invention relates to a circuit for providing overshoot control and damping in a system for providing a high speed driving signal. It is desirable to provide a system which can generate a signal having a fast rise time and only minimal amount of overshoot and ringing.
2. Description of the Related Art
In a system where a fast rise time signal is needed to drive a load having inductive characteristics undesirable signal characteristics can result. For example, where an H bridge type circuit is used to power a load having inductive characteristics, when the current through the load is reversed a large current spike can result in response to the sudden change in current direction. In some applications, such as when supplying a current to drive a magneto-resistive head ("MR head") which is used in a disk drive to orientate the polarity of the disk storage media which is adjacent to the head, a large current spike can cause undesirable effects in the magnetic field which is generated by the MR head. Furthermore, due to potential variation of the MR head elements, the effect of the overshoot can very from one MR head element to another.
A second factor which should also be considered when driving an inductive load with a fast rise time current is that in addition to the current overshoot, a current ringing, or fluctuation, will often follow the overshoot, due to the resonance of the inductive load and its associated stray capacitance. Such current ringing is undesirable in many applications.